Mothers who insist their kids to finish their greens should perhaps add more color to their children?ˉs diet by including strawberries, for a study has found that a natural chemical found in strawberries can boost memory.
Fisetin, a naturally occurring flavonoid commonly found in strawberries and other fruits and vegetables, stimulates signaling pathways that enhance long-term memory, report researchers at the Salk Institute for Biological Studies in this week's Online Early Edition of the Proceedings of the National Academy of Sciences.

"Since the development of a basic understanding of the biochemical pathways involved in memory formation, the holy grail of CNS research in the pharmaceutical industry is the identification of a safe, orally active drug that activates memory-associated pathways and enhances memory," says lead author Pamela Maher, Ph.D., a researcher in the Cellular Neurobiology Laboratory at the Salk Institute.

Maher hit upon the beneficial effects of fisetin when she screened a collection of flavonoids, substances with anti-oxidant activities found in many plants, for their neuroprotective abilities in tissue culture models of neurodegenerative disease.

Maher found that some of those compounds, including fisetin, induced differentiation or maturation of neural cells. Maher explains, "That suggested to us that these compounds might be particularly beneficial, since they might not only protect neural cells from dying but might be able to promote new connections between nerve cells."

The observations that fisetin protects and promotes survival of cultured neurons and boosts memory in healthy mice make it a promising candidate for further studies. Notes Maher, "This is the first time that the function of a defined natural product has been characterized at the molecular level in the central nervous system and also shown to enhance both LTP in vitro and long-term memory in vivo."

"The good news is that fisetin is readily available in strawberries but the bad news is that because of its natural product status there may be little financial interest in getting it into human clinical trials for diseases associated with memory loss such as Alzheimer's, where the treatment options are currently very limited," says Maher.

Besides strawberries, fisetin is found in tomatoes, onions, oranges, apples, peaches, grapes, kiwifruit and persimmons. Gingko biloba leaves, while rich in other flavonoids, do not contain fisetin.

坚持让孩子吃完绿色蔬菜的妈妈们可能应该给孩子的食谱添点别的颜色了，例如红红的草莓，据研究发现，草莓里有一种可以增强记忆的天然化学物质。研究生物学的Salk研究院的研究员在本周的国家科学院在线初版学报上说，草莓和其他水果蔬菜通常含有非瑟酮这种天然类黄酮，它可以刺激增强大脑的长期记忆信号路径。




Pamela Maher博士来自Salk研究院的细胞神经生物学实验室，他说：“因为对含有记忆模式的生化路径基本理解的发展，制药业的CNS研究被认为是安全有效的口服药，它能激活与记忆相关的路径，增强记忆。”



Maher在筛选一组类黄酮时偶然发现了非瑟酮的效用：很多植物里含有抗氧化物质，在细胞组织培养模式下，它能起到神经保护的作用，防止神经退化疾病。


Maher发现，包括非瑟酮在内的某些化合物可以使神经细胞相区别，或者促使神经细胞的成熟。Maher解释道：“这表明，那些化合物可能非常有用，因为它们可能不仅可以保护神经细胞，阻止其死亡，还可能可以促成神经细胞之间新的连接。”



通过实验观察到，非瑟酮对健康实验鼠的神经细胞的生长，增强记忆有保护和促进作用。Maher说：“这是中央神经系统分子水平的自然物质的作用首次被发现，而且表明能增强LTP和长期记忆。”





“好消息就是草莓中含有非瑟酮，坏消息就是用于治疗相关失忆疾病的临床实验可能花费非常大，像老年痴呆症的治疗选择目前就非常有限，因为非瑟酮是种天然物质。”



除了草莓，西红柿、洋葱、橙子、苹果、桃、葡萄、猕猴桃和柿子也含有非瑟酮。银杏叶虽然富含类黄酮，但是却不含非瑟酮。